wall stability question

Hi all, thanks in advance for any advice given.

I'm planning to build a short wall, about six feet long and five feet high. This wall will connect to an existing standard wall and extend to the center of a bathroom, having tile and cement board on the shower side and sheetrock on the other. My question relates to how I should stabilize the wall without connecting the end of the wall in the center of the room to the ceiling? It seems if I bolt it to the wooden floor there would remain a certain amount of instability. I'm thinking of putting L brackets on the floor (with will eventually have cement board, then tile, on it) to then bolt to the wall. I'm just trying to avoid having studs connecting to the ceiling. Well, that's it for now. So, how would you do it?

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wall stability question

If mine, I'd somewhat as mentioned above. If the new wall happened to line up with a wall stud, lag bolt it. Build the new wall leaving the bottom plate only 1 1/2" short. The last stud will be another 8-10 inches longer than the others so it will slip through that 3 1/2 X 1 1/2 hole I cut in the floor and fasten down below.

If I were to have a receptacle(outlet) in the new half wall, I'd leave one side bare for the electric guy. Probably the drywall side.

wall stability question

Once I built a knee wall around a stairwell. I had a similar problem to yours.
I had no access from below, so I had an 'L' bracket made from 1" square steel tubing. I buried the verticle in the Newel post and I knotched the foot into the floor joists and its been solid ever since.

wall stability question

Thanks guys for the replys. I like that idea of the last stud going thru the floor. If I can do that (beams may be in the way) I will add that to the screws, plywood, glue method Ron mentioned. Thanks again!!

wall stability question

Ok... follow up report and question.

I built the wall. It's five feet high and four feet long. It's been plywooded, screwed and glued and lag bolted to a stud on the back wall and also the floor. I also used 3 inch screws for additional stability on the floor. The side of the wall thats in the shower space hasn't been plywooded yet, I'm going to use cement board and tile that. Under the house there wasn't anything handy to bolt the last stud too, so didn't.

However, the wall still wobbles some. I just don't know how much wobble I can get away with. When the cement board goes on, because of a 7 inch dogleg in the back wall, the cement board will tie into the dogleg beyond the pony wall. Does that make sense? I'm sure that will add a bit of stability, but maybe not enough is my guess.

As a note, the wall is pretty stiff, but when forceably moved the wobble is about 1/4 - 3/8 of an inch at the top of the last stud. Sooooo?? Any suggestions?

wall stability question

Quote:

Originally Posted by Alvis

Ok... follow up report and question.

I built the wall. It's five feet high and four feet long. It's been plywooded, screwed and glued and lag bolted to a stud on the back wall and also the floor. I also used 3 inch screws for additional stability on the floor. The side of the wall thats in the shower space hasn't been plywooded yet, I'm going to use cement board and tile that. Under the house there wasn't anything handy to bolt the last stud too, so didn't.

However, the wall still wobbles some. I just don't know how much wobble I can get away with. When the cement board goes on, because of a 7 inch dogleg in the back wall, the cement board will tie into the dogleg beyond the pony wall. Does that make sense? I'm sure that will add a bit of stability, but maybe not enough is my guess.

As a note, the wall is pretty stiff, but when forceably moved the wobble is about 1/4 - 3/8 of an inch at the top of the last stud. Sooooo?? Any suggestions?

Put plywood on both sides of the wall and the cement board over that.
Both legs of the wall should be bolted into framing.
The plywood should be glued and screwed.
Ron

wall stability question

Giz, the house is sort-of octagonal, meaning the blocking between joist would be at odd angles. I suppose not impossible but very difficult given the existance of a heat duct and tight area.

Ron, what legs are you referring? Ive bolted the wall to the floor (sub 1 1/8 " thick) and to the stud at the wall end. The 1/2 ply is glued and screwed. Unfortunatly now I can't remove the ply even if I wanted to replace the end stud to it would go thru floor for anchoring.

What about a steel bracket to go onto the end of the last stud? It could bolt to the floor and the stud. It could be inlayed into the last stud so it didn't interfere with the tile that'll be on the last studs face.

wall stability question

Giz, the house is sort-of octagonal, meaning the blocking between joist would be at odd angles. I suppose not impossible but very difficult given the existance of a heat duct and tight area.

Ron, what legs are you referring? Ive bolted the wall to the floor (sub 1 1/8 " thick) and to the stud at the wall end. The 1/2 ply is glued and screwed. Unfortunatly now I can't remove the ply even if I wanted to replace the end stud to it would go thru floor for anchoring.

What about a steel bracket to go onto the end of the last stud? It could bolt to the floor and the stud. It could be inlayed into the last stud so it didn't interfere with the tile that'll be on the last studs face.

A subfloor is not framing or blocking material. Blocking material is put under the subfloor so the bolts you use sink deep into the material. If the joists are 2x8, you use 2x8 blocking and sink a 6" lag screw with a large washer into it.
Ron

wall stability question

Quote:

Originally Posted by Alvis

Ok... follow up report and question.

I built the wall. It's five feet high and four feet long. It's been plywooded, screwed and glued and lag bolted to a stud on the back wall and also the floor. I also used 3 inch screws for additional stability on the floor. The side of the wall thats in the shower space hasn't been plywooded yet, I'm going to use cement board and tile that. Under the house there wasn't anything handy to bolt the last stud too, so didn't.

However, the wall still wobbles some. I just don't know how much wobble I can get away with. When the cement board goes on, because of a 7 inch dogleg in the back wall, the cement board will tie into the dogleg beyond the pony wall. Does that make sense? I'm sure that will add a bit of stability, but maybe not enough is my guess.

As a note, the wall is pretty stiff, but when forceably moved the wobble is about 1/4 - 3/8 of an inch at the top of the last stud. Sooooo?? Any suggestions?

wall stability question

Right Ron, thanks. The subfloor is merely plywood and I thought that'd be enough... but I guess not. I put up a 45 degree bracket that cut the corner from the 'back' wall to the pony wall. Still a bit of a wobble at the end of the wall though, as the bracket extends a total of 16". I may have to figure out a way blocking the end stud to the joists as you suggest. No easy task

wall stability question

Quote:

Originally Posted by Alvis

Right Ron, thanks. The subfloor is merely plywood and I thought that'd be enough... but I guess not. I put up a 45 degree bracket that cut the corner from the 'back' wall to the pony wall. Still a bit of a wobble at the end of the wall though, as the bracket extends a total of 16". I may have to figure out a way blocking the end stud to the joists as you suggest. No easy task

Can you attach a photo of the lower joist space bay below the wall ???/